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Antimicrobial Synergy Testing by the Inkjet Printer-assisted Automated Checkerboard Array and the Manual Time-kill Method
12:03

Antimicrobial Synergy Testing by the Inkjet Printer-assisted Automated Checkerboard Array and the Manual Time-kill Method

Published on: April 18, 2019

[Effect of combination of hetacillin, cephapirin and amikacin (author's transl)]

M Takahashi, Y Ichiman, Y Usui

    The Japanese Journal of Antibiotics
    |August 1, 1979
    PubMed

    Insights

    The combination of amikacin, cephapirin, and hetacillin showed varied effectiveness against different bacteria. Amikacin demonstrated resistance to common bacterial resistance enzymes, suggesting potential in combating resistant infections.

    Area of Science:

    • Microbiology
    • Pharmacology
    • Bacterial Infections

    Background:

    • Antibiotic resistance is a growing global health concern.
    • Combination antibiotic therapy is explored to enhance efficacy and overcome resistance.
    • Hetacillin, cephapirin, and amikacin are antibiotics with different mechanisms of action.

    Purpose of the Study:

    • To investigate the synergistic effects of combining hetacillin, cephapirin, and amikacin against various bacterial strains.
    • To determine the activity of amikacin against specific bacterial resistance enzymes.
    • To observe the morphological changes in bacteria exhibiting synergistic responses to antibiotic combinations.

    Main Methods:

    • In vitro susceptibility testing of bacterial strains against combinations of hetacillin, cephapirin, and amikacin.
    • Enzyme assays to test amikacin's resistance against penicillinase and cephalosporinase.
    • Electron microscopy to examine ultrastructural changes in bacteria treated with antibiotic combinations.

    Main Results:

    • Antibiotic combination efficacy varied by bacterial genus and species, with concentration-dependent relationships observed.
    • Synergistic effects were noted for amikacin and cephapirin against Escherichia coli and Klebsiella pneumoniae, and amikacin and hetacillin against penicillin-resistant Staphylococci.
    • Amikacin showed resistance to Staphylococcus penicillinase and Escherichia coli cephalosporinase.
    • Electron microscopy revealed cell enlargement and wall destruction in Klebsiella pneumoniae treated with amikacin and cephapirin.

    Conclusions:

    • The combination of hetacillin, cephapirin, and amikacin exhibits variable synergistic activity against different bacteria.
    • Amikacin's resistance to key bacterial enzymes highlights its potential utility in treating resistant infections.
    • Antibiotic-induced morphological damage, such as cell wall disruption, contributes to the observed antimicrobial effects.

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